Automated liquid handling using robotic systems is a technology used for decades in chemical and biochemical fields for reaction preparation and sample processing. Such systems provide a number of advantages, which include high throughput, precision dispensing, labor savings (and attendant cost reduction) and a high degree of repeatability.
One such automated liquid handling system is the AccelBot Mini™ sold by AccelBiotech (Los Gatos, Calif.). This device provides a small footprint system, which is easy to install, self-contained, light weight, yet provides capacity for processing multiple plates and high precision. A hinged cover included as part of the housing allows both a side and top to be exposed, allowing access during loading or maintenance and allowing a sealed system during sample processing. The system includes an x axis track onto which is mounted a y axis arm. Onto y axis arm is mounted a dispensing tool, which may move in the z axis. The dispensing tool is an eight channel pipetting tool, which may include a means for washing the pipettes. The system has a high speed, repeatability and precision, utilizing a 2-phase stepper motor with microstepping in the drive system. The system is controlled by an external computer, allowing a variety of teaching methods for programming the robotic system, including manual input and automated selection. The device has an external interface (e.g. a USB interface) to allow input and output of signals. Temperature control is also provided as part of the system.
Such a workstation combines into a single programmable system the capabilities for automation of a wide range of bioanalytical procedures including: sample pipetting, serial dilution, reagent additions, mixing, reaction timing, washing of reaction vessels, and incubation that requires sealing of the reaction vessel. The work station may include components to transfer, dispense, and aspirate liquid from one location to another automatically in accordance with user programmed instructions.
Workstations of the type described will include a dispense tool mounted such that the tool can be moved in an x-y plane. For example, a tool slidable along a y-axis moving arm, the arm mounted on an x-axis rail, would allow the tool to be positioned at x-y coordinates. This would allow the tool to address locations at one or more locations.
The present x-y robots currently may read to dispense different volumes of liquid, and/or may require a dispense tool (e.g., a pipetting device) that allows for varied spacing of dispense tips. The present embodiments address this need.